Hi,

Again, I have a question from one of my Blog readers, which is related to my previous post:

“Hi Nenad,¸

Thank you very mush. But can you please explain the following inconsistency in MSP behavior:

If in the example you just presented you change a task default calendar’s option None to Standard (Task Information>Advanced<Calendar), the resource John will no longer be scheduled to work on the weekend days 12/03/16 and 13/03/16, and the task will be scheduled as if no exception in John’s calendar for these 2 days making them working for John was made at all, and the task will be finished on 17/03/16 instead 15/03/16.

Why? In my understanding the default task’s calendar option None is referenced to a default Standard Project calendar, so why MSP behaves differently when you leave a default None for the task’s calendar and when you select a Standard calendar instead, even though the two are exactly the same calendar- Standard Project Calendar?

Thank you,
Alex”

First I’m going to create Scenario for this Case in MS PROJECT 2016, and then I will explain it. I will repeat whole previous post, and I will add the explanation for this particular question!

I will create brand new Project with one Task:

As you can see Task will start at Friday 11.03.2016, and since duration is 5 days it will end at Thursday 17.03.2016, because Standard Calendar is used, and weekend is non working time. You can see that here:

If you click on Saturday or Sunday, you will find that From and To field are empty, because those are non working days.

Now I will create John as Resource, and I will assign him to the Task:

and:

As you can see nothing has changed in Start and finish date. Now suppose that John is hard worker and he is supposed to work at Saturday, 12.03.2016, and Sunday 13.03.2016:

Now let’s see Task Usage View:

as you can see Finish date is now Tuesday, 15.03.2016, and John will work during the weekend.

Now, the question from my blog Reader is: WHY? Yes, Standard Calendar is set in a way that each and every Saturday and Sunday are non working days. BUT! If you create Resource in MS PROJECT, and you set a calendar for it (like I did, or in any other possible way), then RESOURCE CALENDAR has higher priority that Project Calendar. And it does make a sense. So, in my example, Project calendar says: “During weekend, work on Tasks will not be performed!”, but since John will work on the Task with exception (he can work on this particular weekend), MS PROJECT Says: “No matter on Project Calendar which says that during weekend  work will not be performed on Tasks, for this particular Task John will work at weekend, because that is written in his instance of Project Calendar, and Task will end sooner!”

Remember: Resource calendar setup has higher Priority than Project calendar setup.

BUT! Now I will assign Standard Calendar to the Task:

and I will get:

as you can see, John will not work during this weekend. The question was: “Why? In my understanding the default task’s calendar option None is referenced to a default Standard Project calendar, so why MSP behaves differently when you leave a default None for the task’s calendar and when you select a Standard calendar instead, even though the two are exactly the same calendar- Standard Project Calendar? “

First of all those Calendars are not same. When I put exception for John, this exception is valid only for John. So, for example if I put Mary on this Task, instead of John, and Mary doesn’t have this exception she is not supposed to work during this particular weekend.

On the other hand when I put Standard calendar (or any other calendar) to the Task it has the highest priority. And, all other exceptions for any particular resources are ignored. you can see that Task has Calendar assigned to it here:

If I want to force that this particular Task should be done during this weekend I must put this exception for the whole calendar, and not only for John’s instance of it:

and I will get the same result as I have got when I changed this for John’s instance of Standard Calendar:

So, where is difference? For example if I have a Task and John will work during the weekend, and Mary will not, and if assign only John to this Task it will take shorter (because he will work during the weekend), than if I assign Mary to it. But if I declare to the whole Standard Calendar that this weekend is working weekend it will apply to all resources (John and Mary, as well) because Task Calendar has the top priority.

I hope that everything is clear now.

Regards.